Forum: ARM programming with GCC/GNU tools Linking two files with 2 mains using objcopy

Author: Opt Em (Company: self) (opt)
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Hi Experts,
I am working in a project to link two files with two mains.
i.e file 1 is having main()
file2 is having main()

Like this:
int main(){
printf("I am from main 1\n");
return 0;

int main(){
printf("I am from main 2\n");
return 0;
Compiling and linking with the help of makefile.

I know this is not possible since linker will throw when it sees 2 mains 
which results in error "Multiple definition".

I tried one way using objcopy to redefine symbols in one file .
i.e file2 sybmols is renamed to main2__main using
"objcopy --prefix-symbols main2_ main2.o".

But after doing this in linker stage it is giving error undefined symbol
main2__main. Why this is coming?
Any one can give there expert opinion?

If any body has a similar makefile can you please share it?
Is there any other alternative way? I don't want to use #ifdef ...#endif 
for any of files since I want this to happen @ at link time.


: Edited by User
Author: Eric (Guest)
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Why do you have two main() routines?
What do you want to achieve with this?
Why don't you just rename one of them into main2()?
Do you realize that the C runtime can only call one main(), so having 
two main()s is doesn't even make sens?


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